Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
  • C08G18/40—High-molecular-weight compounds
  • C08G18/62—Polymers of compounds having carbon-to-carbon double bonds
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
  • C08G18/40—High-molecular-weight compounds
  • C08G18/62—Polymers of compounds having carbon-to-carbon double bonds
  • C08G18/6216—Polymers of alpha-beta ethylenically unsaturated carboxylic acids or of derivatives thereof
  • C08G18/625—Polymers of alpha-beta ethylenically unsaturated carboxylic acids; hydrolyzed polymers of esters of these acids
  • C08G18/6254—Polymers of alpha-beta ethylenically unsaturated carboxylic acids and of esters of these acids containing hydroxy groups
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
  • C08G18/40—High-molecular-weight compounds
  • C08G18/62—Polymers of compounds having carbon-to-carbon double bonds
  • C08G18/6216—Polymers of alpha-beta ethylenically unsaturated carboxylic acids or of derivatives thereof
  • C08G18/622—Polymers of esters of alpha-beta ethylenically unsaturated carboxylic acids
  • C08G18/6225—Polymers of esters of acrylic or methacrylic acid
  • C08G18/6229—Polymers of hydroxy groups containing esters of acrylic or methacrylic acid with aliphatic polyalcohols
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
  • C09D175/00—Coating compositions based on polyureas or polyurethanes; Coating compositions based on derivatives of such polymers
  • C09D175/04—Polyurethanes

Definitions

• Aqueous coating compositions come in particular in the area of top coats. Under top coats are understood to be paints that are used to manufacture the top layer of lacquer can be used.
• the top one Lacquer layer can be single-layer or multi-layer, in particular be two layers.
• Two-coat top coats consist of a pigmented basecoat and one applied to the basecoat film unpigmented or only with transparent Pigments pigmented clear coat.
• Two-coat paints are made today according to the wet-on-wet process manufactured in which a pigmented Basecoat is prepainted and the basecoat layer thus obtained without baking with a clear coat overpainted and then basecoat and Clear coat layer to be cured together.
• This method is economically very advantageous, but provides high demands on the basecoat and the clearcoat.
• the applied to the not yet hardened basecoat Clear lacquer must not dissolve the basecoat or otherwise disrupt, because otherwise paintwork with bad Appearance. This is especially true for paints in which basecoats, the effect pigments (e.g. metal pigments, especially aluminum flakes or pearlescent pigments) used become.
• the top coating compositions with the help of automatic painting systems can be applied by spraying.
• Spray viscosity have such a high solids content, that with 1 to 2 spray coats (cloisters) paint films can be obtained with sufficient layer thickness, and they have to deliver baked paint films that a good appearance (good flow, high gloss, good topcoat level and high hardness) and good weather resistance demonstrate.
• EP-B-358 979 describes aqueous two-component polyurethane coating compositions known the one polyacrylate resin containing hydroxyl groups and a Contain polyisocyanate component. This coating agent are however more transparent when used Top coat over a basecoat, for example in need of improvement with regard to the adhesion to the basecoat film. There are also problems with other mechanical properties of the resulting Coatings, e.g. regarding weather resistance of the resulting coatings.
• JP-OS 4-1254 Coating agents based on hydroxyl groups Polyacrylate resins and crosslinking agents known.
• the hydroxyl-containing ones used as binders Polyacrylate resins are available from monomers containing hydroxyl groups, alkyl acrylates, Alkyl methacrylates, optionally styrene and optionally ethylenically unsaturated polymers. It is essential to the invention that the polyacrylate resin using 4-t-butylcyclohexyl acrylate and / or 4-t-butylcyclohexyl methacrylate manufactured as a monomer component has been.
• This coating agent known from JP-OS 4-1254 exhibit especially when used as a transparent Top coat over a basecoat, especially the The disadvantage of an insufficient pot life of the coating compositions on. Finally, there is the high proportion disadvantage of organic solvents.
• the present invention was therefore the object to provide coating agents, that when used as a clear coat over a basecoat layer the underlying basecoat only if possible dissolve little and a good light / dark effect when viewed from different angles demonstrate.
• the resulting Coatings have good chemical resistance as well have good weather resistance.
• the coating agents should run very well show and under the conditions of car refinishing with the lowest possible proportion organic solvents have good application behavior demonstrate.
• the coating agents for the Car refinishing should be suitable, i.e. they should at low temperatures of generally below 120 ° C, preferably below 80 ° C, be curable.
• the coating compositions should also be at these low Cure temperatures quickly (quick dust and Non-stickiness and quick drying), but at the same time have the longest possible processability (pot life).
• the coating agent have a good topcoat level and when used as a transparent top coat over a pigmented one Basecoat layer for coatings with an improved Adhesion lead to the clear coat.
• the present invention also relates to a Process for the production of a multilayer coating on a substrate surface using of these coating compositions as well as the use of the Coating agent in the field of car refinishing.
• the Coating agents according to the invention when used as a transparent top coat over a pigmented one Basecoat layer have the advantage that they Only slightly dissolve the basecoat and the metal effect influence very little while doing one good chemical resistance and weather resistance exhibit. Furthermore, the invention Coating agents have the advantage of a good topcoat level on and show under the conditions of Car refinishing a very good flow and good application behavior. It is also advantageous that the coating agent at low temperatures are curable and so for the field of car refinishing can be used. Even when hardened of the coating agent at these low temperatures the coatings harden quickly, show but at the same time long processability on. Finally, the coating compositions of the invention when used as a clear coat over a Basecoat layer significantly improved adhesion to Basecoat on.
• Polyacrylate resin is used as component (a1) with (a2), (a3), (a4), (a5) and (a6) copolymerizable from (a2), (a3), (a4) and (a6) different, essentially carboxyl-free ester from (meth) acrylic acid and a cycloaliphatic alcohol containing 6 to 10 Has C atoms, with the exception of cyclohexyl methacrylate, or a mixture of such monomers is used.
• esters of acrylic acid and / or methacrylic acid are cyclohexyl acrylate, 4-tert-butylcyclohexyl acrylate, 4-tert-butylcyclohexyl methacrylate, isobornyl acrylate and isobornyl methacrylate.
• esters of (meth) acrylic acid or a mixture of such (meth) acrylic acid esters are used.
• alkyl acrylates and alkyl methacrylates with up to 20 carbon atoms in the alkyl radical e.g.
• alkyl acrylates are preferred and / or alkyl methacrylates as (a2) component used that at least 20 wt .-% n-butyl and / or t-butyl acrylate and / or n-butyl and / or t-butyl methacrylate exist.
• Ethyl triglycol (meth) acrylate can also be used as component (a2) and methoxy oligoglycol (meth) acrylate with one number average molecular weight of preferably 550 or other ethoxylated and / or propoxylated hydroxyl-free (Meth) acrylic acid derivatives used become.
• Hydroxyalkyl esters are used as examples Acrylic acid, methacrylic acid or another ⁇ , ⁇ -ethylenic called unsaturated carboxylic acid. These esters can be derived from an alkylene glycol, which with the acid is esterified, or they can be reacted the acid obtained with an alkylene oxide become.
• hydroxyalkyl esters can be used primary hydroxyl groups are used; should that Polyacrylate can be less reactive only Hydroxyalkyl esters with secondary hydroxyl groups used become. Mixtures can of course also be used of hydroxyalkyl esters with primary hydroxyl groups and hydroxyalkyl esters with secondary hydroxyl groups be used.
• Suitable hydroxyalkyl esters ⁇ , ⁇ -Unsaturated carboxylic acids with primary Hydroxyl groups are hydroxyethyl acrylate, 3-hydroxypropyl acrylate, Hydroxybutyl acrylate, hydroxyamyl acrylate, Hydroxyhexyl acrylate, hydroxyoctyl acrylate and the corresponding Methacrylates and the corresponding Hydroxy esters of other ⁇ , ⁇ -unsaturated carboxylic acids.
• a secondary hydroxyl group are 2-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, 3-hydroxybutyl acrylate and called the corresponding methacrylates.
• the corresponding esters other ⁇ , ⁇ -unsaturated carboxylic acids e.g. the Crotonic acid and isocrotonic acid are used.
• component (a3) at least partially trimethylolpropane monoallyl ether is used.
• the proportion of trimethylolpropane monoallyl ether is usually 2 to 10 wt .-%, based on the total weight the used to manufacture the polyacrylate resin Monomers (a1) to (a6). But it is next to it also possible, 2 to 10 wt .-%, based on the total weight the used to manufacture the polyacrylate resin Monomers, trimethylolpropane monoallyl ether add to the finished polyacrylate resin.
• the olefinic unsaturated polyols such as in particular trimethylolpropane monoallyl ether, can be the only ones containing hydroxyl groups Monomers (a3), but especially in proportion in combination with other of the above monomers containing hydroxyl groups can be used.
• component (a31) monomers or mixtures of monomers
• component (a3) which, when the respective monomer is polymerized alone, have a polyacrylate and / or polymethacrylate resin with a glass transition temperature of -20 ° C to + 6 ° C, or from + 50 ° C to 80 ° C.
• component (a31) it is of course also suitable to use mixtures which, when component (a31) is polymerized alone, have a polyacrylate and / or polymethacrylate resin with a T g value outside of this for the individual monomers given ranges.
• Component (a31) is preferably selected from Hydroxyethyl methacrylate, hydroxyethyl acrylate, 3-hydroxypropyl methacrylate, 3-hydroxypropyl acrylate, 2-hydroxypropyl methacralate and / or 2-hydroxypropyl acrylate.
• Component (a31) is very particularly preferred.
• component (a3) component (a31) and those already described above, other, different from component (a31) hydroxyl-containing monomers (a32) used.
• One or more may be used as component (a4) Vinyl esters of monocarboxylic acids branched in the ⁇ -position with 5 to 18 carbon atoms in the molecule.
• the branched monocarboxylic acids can be obtained by reacting formic acid or carbon monoxide and Water with olefins in the presence of a liquid, strongly acid catalyst; the olefins can crack products of paraffinic hydrocarbons, such as Mineral oil fractions, and can be both branched such as straight-chain acyclic and / or cycloaliphatic Contain olefins.
• olefins When implementing such olefins with formic acid or with carbon monoxide and water creates a mixture of carboxylic acids, in which the Carboxyl groups predominantly on a quaternary carbon atom sit.
• Other olefinic starting materials are e.g. Propylene trimer, propylene tetramer and diisobutylene.
• the vinyl esters can also on themselves known manner from the acids, e.g. by allowing the acid to react with acetylene.
• Vinyl esters of saturated aliphatic monocarboxylic acids with 9 to 11 carbon atoms on the ⁇ -C atom are branched, used.
• component (a4) if necessary, together with the vinyl ester or instead of the vinyl ester, the reaction product from acrylic acid and / or methacrylic acid with the Glycidyl ester of a monocarboxylic acid branched in the ⁇ -position with 5 to 18 carbon atoms per molecule.
• Glycidyl esters of strongly branched monocarboxylic acids are available under the trade name "Cardura”.
• the Implementation of acrylic or methacrylic acid with the Glycidyl ester of a carboxylic acid with a tertiary ⁇ -carbon atom can be before, during or after the Polymerization reaction take place.
• the reaction product of acrylic and of methacrylic acid with the glycidyl ester of versatic acid used. This glycidyl ester is below that The name "Cardura E10" is commercially available.
• each can have at least one Carrying carboxyl group per molecule, with (a1), (a2), (a3), (a4) and (a6) copolymerizable, ethylenically unsaturated monomer or a mixture of such monomers be used.
• As component (a5) preferably acrylic acid and / or methacrylic acid used.
• other ethylenically unsaturated can also be used Acids with up to 6 carbon atoms used in the molecule become.
• As component (a5) can also Maleic acid mono (meth) acryloyloxyethyl ester, succinic acid mono (meth) acryloyloxyethyl ester and phthalic acid mono (meth) acryloyloxyethyl ester be used.
• component (a6) all with (a1), (a2), (a3), (a4) and (a5) copolymerizable, of (a1), (a2), (a3) and (a4) various, essentially carboxyl-free ethylenically unsaturated monomers or mixtures be used from such monomers.
• a component (a6) are preferably vinyl aromatic hydrocarbons, such as styrene, ⁇ -alkylstyrene and vinyltoluene, used.
• component (a6) can be used in combination with others monomers suitable as component (a6)
• Polysiloxane macromonomers can be used. Suitable are polysiloxane macromonomers that are number average Molecular weight from 1,000 to 40,000, preferably from 2,000 to 10,000, and on average 0.5 to 2.5, preferred 0.5 to 1.5, ethylenically unsaturated double bonds have per molecule.
• polysiloxane macromonomers that are number average Molecular weight from 1,000 to 40,000, preferably from 2,000 to 10,000, and on average 0.5 to 2.5, preferred 0.5 to 1.5, ethylenically unsaturated double bonds have per molecule.
• component (a6) preference is also given to using polysiloxane macromonomers which have been prepared by reacting from 70 to 99.999 mol% of a compound (1) represented by the formula (I) in which R 1 represents an aliphatic hydrocarbon group with 1 to 8 C atoms or a phenyl radical and R 2 , R 3 and R 4 each represent a halogen radical or an alkoxy radical with 1 to 4 C atoms or a hydroxyl group, with 30 to 0.001 Mol% of a compound (2) represented by the formula (II) in which R 5 represents a hydrogen atom or a methyl radical, R 6 , R 7 and R 8 each represent halogen, OH or an alkoxy radical having 1 to 4 carbon atoms or an aliphatic hydrocarbon group having 1 to 8 carbon atoms, at least one of the radicals R 6 , R 7 or R 8 is OH or an alkoxy group and n represents an integer from 1 to 6.
• Examples of suitable compounds (1) and (2) are in WO 92/22615 on page 13, line 18 to page 15, Line 9.
• the reaction between compounds (1) and (2) is accomplished by the dehydrating condensation of the hydroxyl groups contained in these compounds are and / or the hydroxyl groups, which on the Hydrolysis of the alkoxy groups of these compounds attributed are. Depending on the reaction conditions involves the implementation in addition to the dehydration reaction a deal-coherent condensation. If the compounds (1) or (2) halogen radicals contain, the reaction between (1) and (2) accomplished by dehydrohalogenation.
• the amount of the polysiloxane macromonomer (s) used (a6) for modifying the acrylate copolymers (A) is less than 5% by weight, preferably less than 3 % By weight, particularly preferably 0.05 to 2.5% by weight, and very particularly preferably 0.05 to 0.8% by weight, in each case based on the total weight of the to produce the Copolymer (A) monomers used.
• the production of the polyacrylate resins used according to the invention (A) is carried out in an organic solvent or solvent mixture and at least in the presence a polymerization initiator.
• a polymerization initiator are used for the production of polyacrylate resins usual and for suitable for the preparation of aqueous dispersions Solvents and polymerization initiators used.
• Examples of usable solvents are butyl glycol, 2-methoxypropanol, n-butanol, methoxybutanol, n-propanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, Ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, Diethylene glycol monoethyl ether, Diethylene glycol diethyl ether, diethylene glycol monobutyl ether, 2-hydroxypropionic acid ethyl ester and 3-methyl-3-methoxybutanol and derivatives based on Propylene glycol, e.g. Ethyl ethoxypropionate, methoxypropylacetate and the like.
• Propylene glycol e.g. Ethyl ethoxypropionate, methoxypropylacetate and the like.
• useful polymerization initiators free radical initiators such as e.g. t-butyl perethyl hexanoate, benzoyl peroxide, azobisisobutyronitrile and called t-butyl perbenzoate.
• the polymerization expediently at a temperature from 80 to 180 ° C, preferably 110 to 140 ° C, performed.
• Preferred solvents are ethoxyethyl propionate and butyl acetate used.
• component (a4) submitted together with at least part of the solvent and add the remaining components.
• component (a4) can only partially together with at least part of the solvent in the template will be given and the rest of this component be added as described above.
• P refers for example, at least 20 wt .-% of the solvent and about 10% by weight of component (a4) and, if appropriate Parts of components (a1) and (a6) submitted.
• the production of the invention is also preferred polyacrylate resins (A) used by a two-stage process, where step (I) lasts from 1 to 8 hours, preferably 1.5 to 4 hours, and the addition the mixture of (a5) and the rest of the Components (a1), (a2), (a3), (a4) and (a6) within from 20 to 120 minutes, preferably within 30 to 90 minutes. After the addition of Mixture of (a5) and any remaining components (a1), (a2), (a3), (a4) and (a6) become so long polymerized further until all monomers used have been substantially fully implemented.
• the amount and rate of addition of the initiator will preferably chosen so that a polyacrylate resin (A) with a number average molecular weight of 1,000 to 7,000, preferably 1,800 to 5,000 is obtained. It it is preferred to add the initiator at the same time how to start adding the monomers and about half an hour after the addition of the monomers has been ended to end. The initiator is preferred added in a constant amount per unit of time. When the addition of initiator is complete, the reaction mixture for as long (usually 1 1/2 hours) Polymerization temperature held until all used Monomers essentially completely implemented have been.
• the polyacrylate resin (A) obtained has an OH number from 40 to 200, preferably 60 to 140 mg KOH / g, a Acid number from 20 to 100 mg KOH / g, preferably 25 to 50 mg KOH / g.
• the one obtained particularly preferably has Polyacrylate resin (A) also has a glass transition temperature from -40 to + 60 ° C, preferably -20 to + 40 ° C, on.
• the Tg value of the homopolymer of the reaction product Acrylic acid and Cardura E10 equal the glass transition temperature of the homopolymer of isodecyl methacrylate (-41 ° C).
• the resultant Polyacrylate resin partially neutralized and in water dispersed.
• the degree of neutralization to be set depends on the acid number of the acrylate and is in general at acid numbers ⁇ 70 mg KOH / g between 50 and 90% and with acid numbers> 70 mg KOH / g between 30 and 80%.
• Primary, secondary and tertiary are preferred Amines such as Ammonia, ethylamine, propylamine, Dimethylamine, dibutylamine, cyclohexylamine, benzylamine, Morpholine, piperidine, diethanolamine and triethanolamine used.
• Tertiary amines are particularly preferred used as neutralizing agent, especially dimethylethanolamine, Triethylamine, dimethylisopropylamine, Tripropylamine and tributylamine.
• the neutralization reaction is generally carried out by Mix the neutralizing base with the polyacrylate resin carried out. This is preferably as much base used that the top coating composition a pH of 7 to 8.5, preferably 7.2 to 7.8, having.
• Polyacrylate resin particles their average particle size is preferably between 60 and 300 nm (measurement method: Laser light scattering, measuring device Malvern Autosizer 2 C).
• the polyacrylate resin (A) used according to the invention is usually in a coating in the coating Quantity from 30 to 50% by weight (calculated as a solid, i.e. without water content), based on the total weight of the coating agent used.
• the polyisocyanate component (B) is any organic polyisocyanates with aliphatic, cycloaliphatic, araliphatic and / or aromatic bound, free isocyanate groups.
• polyisocyanates with 2 to 5 isocyanate groups per molecule and with viscosities from 200 to 2000 mPas (at 23 ° C) used.
• the polyisocyanates still small amounts of organic solvent, preferably 1 up to 25% by weight, based on pure polyisocyanate, be added so as to incorporate the To improve isocyanates and possibly the viscosity of the Polyisocyanates to a value within the above Lower areas.
• suitable solvents for the polyisocyanates are, for example Ethoxyethyl propionate, methoxypropyl acetate and similar.
• Suitable isocyanates are, for example in "Methods of Organic Chemistry", Houben-Weyl, volume 14/2, 4th edition, Georg Thieme Verlag, Stuttgart 1963, Pages 61 to 70, and by W. Siefken, Liebigs Ann. Chem. 562, 75 to 136.
• Suitable for example are 1,2-ethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, 2,2,4- or 2,4,4-trimethyl-1,6-hexamethylene diisocyanate, 1,12-dodecane diisocyanate, ⁇ , ⁇ '-diisocyanatodipropyl ether, cyclobutane-1,3-diisocyanate, Cyclohexane-1,3- and -1,4-diisocyanate, 2,2- and 2,6-diisocyanato-1-methylcyclohexane, 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (isophorone diisocyanate "), 2,5- and 3,5-bis (isocyanatomethyl) -8-methyl-1,4-methano-decahydronaphthalene, 1,5-, 2,5-, 1,6- and 2,6-bis (is
• polyisocyanates can also isocyanurate groups and / or biuret groups and / or Allophanate groups and / or uretdione groups and / or Having urethane groups and / or urea groups Polyisocyanates are used. Having urethane groups Polyisocyanates are, for example, by Reaction of some of the isocyanate groups with polyols, such as. Trimethylolpropane and glycerin.
• Aliphatic or cycloaliphatic are preferred Polyisocyanates, especially hexamethylene diisocyanate, dimerized and trimerized hexamethylene diisocyanate, Isophorone diisocyanate, dicyclohexylmethane-2,4'-diisocyanate or dicyclohexylmethane 4,4'-diisocyanate or mixtures of these polyisocyanates are used. Mixtures of uretdione are very particularly preferred.
• the Polyisocyanate component (B) can also from the rest any mixtures of the polyisocyanates mentioned by way of example consist.
• aqueous two-component polyurethane coating agents will the Polyisocyanate component (B) shortly before application mixed with the polyacrylate resin component (A).
• the Mixing can be done by simply stirring at room temperature, but also done by dispersing.
• the Polyisocyanate component (B) is in such a Amount used that the weight ratio between Polyacrylate resin solid and polyisocyanate solid 60:40 to 90:10, particularly preferably 70:30 to 85:15, is.
• the ratio of the number of free OH groups component (A) to the number of isocyanate groups component (B) is usually in the range from 1: 2 to 2: 1.
• aqueous two-component polyurethane resin coating compositions according to the invention can in addition to the invention used polyacrylate resin (A) also crosslinked polymer microparticles, as described, for example, in EP-A-38127 and / or one or more compatible resins, e.g. water-dilutable or water-soluble polyacrylate resin (s), polyurethane resin (s), Polyester resin (s), alkyd resin (s) or epoxy resin ester contain.
• the proportion of this (s) further Resins (s) are usually between 0 and 25% by weight, preferably between 0 and 15% by weight, in each case based on the total weight of the coating material and the Solids content of the binder.
• the coating compositions of the invention for example up to 30 wt .-%, based on the binder solid the polyacrylate resin (A), one means Emulsion polymerization produced acrylate with an OH number, preferably between 40 and 200 mg KOH / g is added.
• the production of such Emulsion polymer is for example in the DE-OS 40 09 000 described, but the OH number of the acrylates is to be increased accordingly.
• Examples of the monomer components (m1) to (m6) suitable connections are those in the description of the acrylic resin (A) listed compounds.
• the coating compositions of the invention also common auxiliaries and additives, such as in particular thickeners and wetting agents.
• thickeners and wetting agents such as in particular thickeners and wetting agents.
• Coating agents a nonionic polyurethane thickener added as this will be a better one Transparency and better emulsifiability of the polyisocyanate leads.
• aqueous coating compositions also a wetting agent based on an alkyl modified polyether added, as this also increases the transparency of the Coating agent as well as gloss and flow of the Coating agent improved.
• auxiliaries and additives such as Defoamers and the like.
• the amount of auxiliaries and additives is usually between 0.01 and 10 wt .-%, based on the total weight the coating agent.
• aqueous coating compositions according to the invention can also contain common organic solvents. Their share is kept as low as possible. He is lying usually less than 15% by weight, preferably 2 to 10% % By weight, based in each case on the total weight of the Coating agent.
• esters e.g. Ethyl glycol acetate, butyl glycol acetate, Ethyl diglycol acetate, ethyl ethoxypropionate, methoxypropylacetate etc.
• the paints according to the invention are generally based on set a pH between 6.5 and 9.0.
• the pH can be adjusted with conventional amines, e.g. Triethylamine, Dimethylaminoethanol and N-methylmorpholine become.
• the paints according to the invention can be applied by customary application methods, such as. Spraying, knife coating, painting, Dipping on any substrates, e.g. Metal, Wood, plastic or paper.
• the Lacquers according to the invention are preferably used for production of topcoats used.
• the invention Varnishes can be used for both series and also in the refinishing of automobile bodies be used. However, they are preferred in Used in the field of refinishing.
• the invention aqueous coating agents can be used as Filler and for the production of single-layer top coats as well as pigmented basecoats or as clearcoats in a process for producing a multilayer Painting can be used (base coat / clear coat method).
• paints according to the invention for the production of single-layer top coats or as basecoats then they can be used with pigments such as e.g. Inorganic-based pigments, e.g. Titanium dioxide, Iron oxide, soot, etc. and / or pigments organic base and / or metal pigments, e.g. Aluminum bronzes and / or pearlescent or interference pigments, be pigmented.
• Aluminum bronzes and Pearlescent or interference pigments are examples of Effect pigments.
• Varnishes that do not contain pigments or are only transparent are pigmented, overpainted, they can but also with conventional clear coats based on organic solvents, with aqueous clear coats or powder clear coats can also be overcoated.
• lacquers according to the invention are preferred as Clear varnishes used.
• basecoats used in this process are known and therefore do not need to be explained in more detail become.
• suitable basecoats are also those in DE-A 41 10 520, DE-A 40 09 000, the DE-A 40 24 204, EP-A-355 433, DE-A 35 45 618, DE-A 38 13 866 and DE-A-42 32 717.2 Basecoats.
• Basecoats characterized by this are those that have not yet been published German patent application P 43 27 416.1 described Basecoats characterized by this are that they are a hydroxyl-containing polyester with a weight average molecular weight Mw of 40,000 - 200,000 and a non-uniformity Mw / Mn> 8 contain and that for the production of the polyester at least 50% by weight of aromatic dicarboxylic acids or their derivatives capable of esterification have been used, however, the maximum content of phthalic anhydride is 80 Is wt .-% and where the wt .-% information in each case the total weight of the polyester used acid components are related.
• the coating compositions of the invention stand out in particular through good adhesion to the basecoat, good scratch resistance and high hardness resulting coatings.
• the Coating agents dry quickly while at the same time long processability (pot life). Farther show the resulting coatings, in particular in the case of clear coat, good mechanical Properties, such as good gloss retention, a good fullness and a good flow.
• the paint thus obtained is then phosphated and coated steel sheets applied.
• the phosphated Steel sheets are used for this with a commercially available conventional filler (commercial product Glasurit basic filler EP 801-1552 from Glasurit GmbH, Weg, with an epoxy functional binder and a amino functional hardener) by spray application coated (dry film thickness approx. 40 to 60 ⁇ m), Dried for 45 min at 80 ° C and 16 h at room temperature and wet with sandpaper P800 and random orbit sander ground.
• a basecoat is made from a Mixture of 80 parts of a commercially available conventional Metallic basecoat (commercial product basecoat AE 54M 99/9 basic color aluminum super fine Glasurit GmbH, Weg) based on a hydroxyl group Polyester, cellulose acetobutyrate, Wax and a melamine resin and 20 parts of another conventional basecoat (Commercial product base coat AE 54M 552 base color helioblue from Glasurit GmbH, Weg) on the basis of a hydroxyl-containing polyester, cellulose acetobutyrate, Wax and a melamine resin applied by first a spray coat is applied and after one Second flash-off time of 5 min is applied (spray pressure 4 - 5 bar each).
• the dry film thickness of the basecoat is approx. 20 ⁇ m. After a flash-off time of 30 min. becomes the clear coat applied by first applying a spray coat and after an intermediate flash-off time of 3 min second spray coat is applied (spray pressure 4 - 5 bar each). The boards are then depending on carried out test under different conditions dried. The dry film thickness of the clear coat is approx. 50 - 80 ⁇ m.
• the light / dark alternation between top view and oblique view should be as pronounced as possible.
• the supervision is OK if the board with the test clear coat is the same or greater brightness than the standard panel having.
• the oblique view is fine if the board with the test varnish is the same or one lower brightness than the standard panel.
• the lacquered board is covered with an approx. 3 cm 2 sheet of paper.
• a small plate made of hard plastic is placed on this paper, on which a weight of 100 g is then placed.
• it is checked whether the paper is still adhering. The test is repeated every 15 minutes, shortly before the tack is reached, the repetition interval is shortened to 5 minutes
• the clear lacquer is applied to phosphated, coated steel sheets which are coated with the filler and basecoat described above and dried at room temperature. After 24 hours of storage at room temperature, gasoline resistance is tested for the first time.
• a cotton pad filter grade, type T950, size 2.3 from Seitz
• 1 ml of premium petrol lead-free
• the structure caused by the swelling of the paint surface is assessed visually: not marked, marked, very lightly marked, slightly marked, marked, strongly marked, very strongly marked.
• the period of storage at room temperature in days after which the petrol test is OK, ie no marking is visible, is indicated.
• the viscosity is the expiry time in DIN 4 cups measured at 20 ° C.
• the coating compositions of Examples 1 to 6 lead to Coatings with a good top coat level, high Hardness and high gloss. Good is also advantageous Transparency and that the basecoat is not dissolved.
• the clear coat E1 of Example 1 shows sufficient Adhesion with good drying.
• the light / dark change of the Basecoat is good.
• the clear varnish shows V1 of comparative example 1 poorer drying, poor petrol resistance and easy resolution of the basecoat.
• the light / dark change is no longer sufficient.
• Example 2 shows that Clear coat of Example 1 has a significantly better adhesion.
• the light / dark change of the basecoat is good.
• drying is slower than that of clear coats of Example 1 and Comparative Example V1.
• Example 3 shows compared to the clear coat Example 1 has a significantly better adhesion.
• the Light / dark change of the basecoat is good.
• drying is slower than that of clear coats of Example 1 and Comparative Example V1.
• the clearcoat of comparative example V2 shows sufficient Liability. The light / dark change of the basecoat is not enough.
• the clear coat of example E6 shows a worse one Liability as that of Examples E1 to E4, but the against the adhesion of the clearcoat of the comparative example V3 is significantly improved. The light / dark change the basecoat is good.

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• Organic Chemistry (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Wood Science & Technology (AREA)
• Paints Or Removers (AREA)
• Application Of Or Painting With Fluid Materials (AREA)
• Polyurethanes Or Polyureas (AREA)

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• 1994
  • 1994-11-07 DE DE4439669A patent/DE4439669A1/de not_active Withdrawn
• 1995
  • 1995-10-25 ZA ZA959032A patent/ZA959032B/xx unknown
  • 1995-10-28 BR BR9509621A patent/BR9509621A/pt not_active IP Right Cessation
  • 1995-10-28 EP EP95936564A patent/EP0791025B1/de not_active Expired - Lifetime
  • 1995-10-28 AT AT95936564T patent/ATE211152T1/de not_active IP Right Cessation
  • 1995-10-28 DE DE59509973T patent/DE59509973D1/de not_active Expired - Fee Related
  • 1995-10-28 ES ES95936564T patent/ES2169769T3/es not_active Expired - Lifetime
  • 1995-10-28 US US08/836,869 patent/US5876802A/en not_active Expired - Fee Related
  • 1995-10-28 WO PCT/EP1995/004234 patent/WO1996014348A1/de not_active Application Discontinuation
  • 1995-10-28 JP JP51501796A patent/JP4159600B2/ja not_active Expired - Fee Related
  • 1995-10-28 KR KR1019970703030A patent/KR970707197A/ko not_active Application Discontinuation

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